In a speech to the European Economic and Social Committee, the EU chief negotiator Michel Barnier warned that the UK cannot possibly enjoy the benefit of the single market or frictionless trade with the EU after it leaves the EU. Mr Barnier said that these points have been made very clear but he is not sure “whether they have been fully understood across the Channel.”

“I have heard some people in the UK argue that one can leave the single market and build a customs union to achieve “frictionless trade” – that is not possible. The decision to leave the EU has consequences.”

These comments are in stark contrast to the UK’s negotiating position which seeks trade with the EU to be as frictionless as possible.

Mr Barnier said he wanted to be clear. “‘No deal’ would mean that our trade relations with the United Kingdom would be based on World Trade Organisation rules. There would be customs duties of almost 10% on vehicle imports, an average of 19 % for alcoholic beverages, and an average of 12% on lamb and also fish, for which the vast majority of British exports go to the EU.

On the border issue, Mr Barnier said “While leaving the customs union would in any case involve border formalities, ‘no deal’ would mean very cumbersome procedures and controls.”